Bud Blight

Symptoms:

  • Young plants can be stunted.
  • The terminal bud of plants at various ages can be bent over to form a characteristic hook, and buds may become brown and fall off.
  • The pith may develop a brown discoloration, and leaflets may be smaller than normal and may deform by cupping.
  • Pods may have brown patches and may develop poorly and abort.
  • Maturity can be delayed and plants may remain green until frost.

Pathogen Involved:

  • Tobacco ringspot virus (TRSV).
  • Seed transmission is the most important route for transmission, but thrips, grasshoppers, and dagger nematodes may be involved with transmission as well.
  • This virus has a wide host range including pea, common bean, and red clover.

Time of Occurrence:

  • All season.

Conditions Favoring Disease:

  • Fields next to clovers, pastures, and weedy areas.

Disease Management:

  • Plant virus-free seed.
  • There are differences in resistance levels among some soybean varieties.
  • It may be helpful to avoid planting soybeans next to pastures to reduce spread of the virus to soybean fields.